Various forms of cyclone-type classifiers have heretofore been utilized for classifying various types of fluid flow suspended materials. Some forms of cyclone-type classifiers are specifically adapted to classify materials suspended in a gas flow and other cyclone classifiers are particularly well adapted to classify materials suspended in a liquid flow.
Conventionally, cyclone classifiers include generally cylindrical housings disposed in upstanding position and closed at their lower ends by means of upwardly opening frusto-conical lower end walls including central restricted outlets. Upper portions of the housings include inlet structures for admitting fluid flow suspended materials into the interiors of the housings along paths extending generally tangentially of the chambers and tubular "vortex finders" project centrally downwardly into the interiors of the housings and terminate downwardly at a level spaced intermediate the inlet structures and the upwardly opening frusto-conical walls closing the lower ends of the housings.
In order to variably adjust the classifying capabilities of cyclone classifiers, the restricted outlets formed in the apex portions of the frusto-conical closure walls may be varied in effective cross-sectional area and may be varied in longitudinal cross-sectional profile. In addition, the vortex finders may also be adjusted longitudinally of the housings in order to further vary the classifying aspects of a cyclone-type classifier.
Various forms of cyclone classifiers of the immediately above set forth types are disclosed in U.S. Pat. Nos.: 3,057,476, 3,087,645, 3,136,723, 3,353,673, 3,455,450, 3,887,456, 3,902,601 and 3,926,787.